Amazon cargo plane crash in Miami: what the recorders now show

What the recorders now show

NTSB investigator Chihoon Shin said the nose gear and right main landing gear first contacted the runway at a recorded ground speed of 158 knots. The left main landing gear did not contact the pavement until 11 seconds later. Engine power then increased to values consistent with go-around thrust.^3,8

The attempted go-around did not continue. Eleven seconds before the recording ended, the throttles were reduced to idle and the brakes were reapplied. Recorded data showed no indication that the speed brakes or thrust reversers deployed during the rollout.^4,6,8

The cockpit recording adds another piece that was not public when the first version of this report was written: one pilot repeatedly raised concern about excessive speed as the aircraft descended, while automated alerts including sink-rate and terrain warnings sounded. The crew nevertheless continued the approach. Investigators are now focused in part on why an unstable approach was continued and why the go-around was started only after touchdown and then abandoned.^2,3,6,7

What changed from the first version of this report

On September 7, the exact touchdown sequence, verified speed profile, use of the speed brakes and thrust reversers, and whether the crew attempted a go-around were still open questions. They are no longer wholly unknown. The NTSB has now released specific recorder-derived facts about each of them.^6,8

What remains unresolved is the explanation. The data show what the aircraft and crew did in the final seconds; they do not yet establish why the crew persisted with the approach, why the go-around was abandoned, whether aircraft systems behaved as commanded, or how weather, training, procedures and crew coordination contributed.^2,3,4,6,7,8

The runway-safety question

Miami's runway had the federally compliant safety area required beyond the pavement, but it did not have an Engineered Materials Arresting System, or EMAS, designed to slow an aircraft that overruns a runway. Investigators are examining the absence of such a system as part of the accident review.^1,3,9

That does not establish that an arresting system would have prevented the deaths. The aircraft traveled roughly 1,300 feet beyond the runway before coming to rest, and the NTSB has not issued a conclusion about what difference EMAS would have made in this crash.^2,9

The aircraft, crew and operator

The aircraft was a 32-year-old Boeing 767-33A freighter operated by 21 Air for Amazon Prime Air and converted from passenger to cargo service. Investigators have said they will examine the aircraft's maintenance and performance as well as the crew's experience and training and the operator's procedures. Age alone is not evidence of a cause.^2,3,5,6

Reuters reported that the pilots had substantial overall flight experience but were comparatively recent 767 type-rating holders. The NTSB's latest disclosures have put crew coordination and decision-making squarely into the investigation, but that is still an investigative line rather than a final finding of cause.^2,4,6,7